Got a used plane, needed recovering, stripped monokote off, found extensive oily spots. Laid on strips of newsprint, put a covering iron to it set at max temp, amazing how much oil soaked up into the paper. Repeated until just a little oil was coming up. At that point laid on more strips of paper, saturated the paper with denatured alcohol (dripped on from a plastic pipette). Let the alcohol soak into the wood for a few minutes, then hit that with the iron (still at max temp setting, which is not hot enough to ignite the alcohol.) This is sort of like steam-cleaning your balsa. Alcohol evaporates quickly under heat of the iron, draws out whatever oil is still in the wood. As soon as that process was complete, tried a practice patch of monokote with iron set at 1-1/2, covering stuck pretty good. No long waiting, done in less than an hour. Paper towel would probably work as well.